I apologize if my question was ambiguous. Let me break it down.
Suppose I have a polymer fiber-reinforced composite. Now the effective elastic properties of this composite will be anisotropic which means I will need 21 coefficient (Cijkl) of the elastic stiffness matrix for this composite. Now if I have a nanoparticle reinforced polymer composite and the shape of the nanoparticles are spherical and distributed uniformly in the polymer, then how many coefficients of the elastic stiffness matrix do I need to analyze the model.
Thanks in advance.